As the number of interfaces within a single hardware cabinet or enclosure increases, it becomes increasingly difficult to control and contain the electromagnetic emissions radiated out of the enclosure. Similarly, as traffic rates increase of the devices within the enclosure, it becomes increasingly difficult to control and contain the electromagnetic emissions radiated out of the enclosure.
This issue is likely to become even more pronounced as traffic rates jump from 10 Gbps to 25 Gbps, and beyond, and wavelengths of the associated radio frequency (RF) radiation shrink. Shorter wavelength RF radiation may effectively use small openings in the enclosure as a slot antenna, transmitting the RF radiation beyond the enclosure and into the environment of the enclosure. Accordingly, RF leakage may be more pronounced at certain points of an enclosure, such as at a vented top.
Various regulatory agencies promulgate standards that limit the radiated emissions from hardware devices, such as servers and switches, and the enclosures that contain these devices. Some of these standards may be difficult to meet at particular frequencies. For example, switches operating at 10 Gbps may result in a substantial amount of radiation leakage at approximately 10 GHz.
Various solutions exist that attempt to mitigate or eliminate transmission of RF radiation. These solutions include enclosure gaskets, shielding, and other absorption materials. Use of these solutions can be cumulatively expensive, and may not be adequate for successfully passing radiated emissions testing.